NSF-funded project to study multiscale high-speed impacts on materials

By Cassie Montgomery

Published: May 27, 2020 3:53:00 PM

Vinamra Agrawal Vinamra Agrawal

High speed impacts occur often in the aerospace and defense industries – from a bird striking an airplane to a micrometeorite colliding with a satellite. Understanding how materials such as plastics, metals and ceramics that make up airplanes and satellites respond to high-speed impacts can help engineers to design strong, lightweight and impact-resistant structures.

Traditionally, high-speed impact behavior has been studied using one of two methodologies, and each is limiting in its own way. One tries to study the problem exclusively at the atomic scale. The other studies the problem at the meter scale. 

An Auburn University assistant professor of aerospace engineering is proposing to evaluate the problem looking at both the atomic scale and the meter scale. Vinamra Agrawal has been awarded a 3-year, $408,000 National Science Foundation grant for the project titled “Concurrent multiscale moving-window scheme for shock wave propagation and microstructural interaction.”

“An atomic scale approach cannot study realistic-sized problems, and the meter-scale approach loses information at micro and nanoscales,” he said. “This work attempts to circumvent challenges presented by either of these two approaches.”

He will be developing a new computational framework where larger and smaller length scales are simultaneously modeled in the same problem.

“Since this framework is new, it requires careful and systematic validation and verification,” he said. “Thankfully, extensive studies exist at atomic scales and meter scales that can be used to validate and verify the framework. Moreover, there is an active community performing high speed impact experiments on materials. The computational framework developed in this work will be validated against experimental literature and verified against existing atomic and meter-scale simulation frameworks.”

Agrawal will be collaborating with the Center for Polymer and Advanced Composites, the National Center for Additive Manufacturing Excellence and the Department of Geosciences to obtain polymers, polymer composites, additively manufactured metals and geological specimens to study in a laboratory setting. Using a Split-Hopkinson Pressure bar, he will subject each of these materials to impact compression.

One goal of the project is to engage students of all ages through engineering outreach activities facilited through the Samuel Ginn College of Engineering, such as E-Day and the Engineering as Art exhibit.

“The project aims to engage K-12 students through outreach activities and spark their interest in materials science and the complex, yet beautiful, mechanics of materials. The project also aims to engage undergraduate students in materials science research. By working on various aspects of this framework, this work will not only expose undergraduate students to state of the art research, but also provide opportunity to be part of the active research community,” he said.

Ultimately, Agrawal’s research in this area has the potential to make a substantial impact in the manufacturing sector.

“With advancements in modern manufacturing, it is now possible to control a material's structure at the microscale and nanoscale, essentially designing a material from the ground up,” he said. “This work provides a way to understand the mutiscaled nature of materials, which will help towards designing lightweight impact resistant structures in the future.”

 

Media Contact: Cassie Montgomery, cmontgomery@auburn.edu, 334-844-3668

Recent Headlines